When visiting Yosemite there are many sites to see, such as the sheer face of Half Dome turning gold as the sun sets, Yosemite Falls at full throttle and tiny ants climbing up the nose of El Capitan.

The ants aren’t really ants, of course; they’re people who look like ants as they ascend the imposing 1,900-foot face of this granite monster (about 2¼ Transamerica Pyramids on top of each other).

To a non-climber it seems like one of the most foolhardy things a person could do. From the ground it looks nearly impossible to scale such a vertical face, with numerous opportunities to fall to your death.

But to a climber, it’s one of the ultimate challenges – the most famous “big wall” route in the world. It’s a Grade 6, meaning that it should take six days to ascend for a party of competent climbers.

And to Hans Florine of Lafayette, it’s an opportunity to get into the speed climbing record book. In October he and Yuji Hirayama ascended the gray icon in two hours, 37 minutes and five seconds – less time than it takes some East County residents to get to work on especially congested mornings.

Florine, 44, visited REI in Brentwood recently to discuss and show photos and a video of his record-setting climb. He began by discussing the 51-year history of climbing El Capitan.

“In the ’50s, people thought it was impossible – truly they used the word ‘impossible’ – to climb such a big, vertical wall,” he said. “Because you couldn’t haul enough food, water and gear up there to survive.”

The impossible was first performed in November of 1958 by three climbers who took 45 days to make it to the top. Over the next 17 years climbers were able to reduce the number of days on the face, but it wasn’t until 1975 that it was conquered in one day (17 hours and 40 minutes).

“Which was really cool, because this was still considered a Grade 6,” said Florine. “The average competent party was still taking three to seven days to climb this route.”

It took 13 years to break the 10-hour barrier; four more years to break the five-hour barrier. It wasn’t until 2001 that the four-hour barrier was broken by Florine and Peter Croft and then reduced the following year to under three hours (2:48.50) by Florine and Hirayama.

That record stood for five years until it was broken by two professional-climbing German brothers, Alexander and Thomas Huber. For the past two years there’s been a friendly rivalry between the dueling duos to shave seconds and minutes off of the record.

Florine has also solo climbed El Capitan in just under 12 hours – a grueling process that requires him in effect to climb it 2½ times because he must rappel back down to undo his climbing gear as he ascends. And he has solo-ascended both Half Dome and El Capitan in one day, one of only two people to achieve that.

Florine was asked whether the Huber brothers are planning to beat his record. “I don’t know,” he said, then joking, “I hope they don’t embarrass themselves by trying to do that again” in reference to the Hubers having made a film of one of their unsuccessful attempts to break his record.

Another person in the audience of about 30 in REI’s community room asked Florine if he considered himself at the top of his climbing now.

“I kind of got my sights set on doing the Alcatraz swim this year. Because I’m at the bottom of the barrel in swimmers and have a long way to go,” he replied. “I think I was a better, faster athlete in 1990. But that’s what’s cool about climbing: knowledge and experience are worth way more, apparently, than brutish youth and strength.”

The next event in the monthly speaker series at the REI in the Streets of Brentwood shopping center on May 21 will focus on hiking the John Muir Trail. For more information, go online to www.rei.com/stores/126.